The aim of this work is to evaluate the capability of tomato plants to use different Fe sources, such as Fe citrate, Fe phytosiderophores, and Fe complexed by a water-extractable humic substances (Fe-WEHS) also in re- lation to physiological and molecular adaptations induced by these complexes at the root level. Tomato plants acquired higher amounts of Fe from Fe-WEHS than from the other two sources and this phenomenon occurred only when the treatment lasted 24 h. The higher acquisition of Fe from Fe- WEHS than other sources depended on a reductive mecha- nism and on rhizosphere acidification and appeared to be due neither to a higher apoplastic loading nor to a higher resistance of WEHS to microbial degradation. Supply of the different Fe complexes to deficient plants induced a tran- sient upregulation of Fe(III)-chelate reductase (LeFRO1) and Fe transporter genes, LeIRT1 and LeIRT2. In Fe- WEHS-fed plants, where a quicker and higher upregulation of these genes was evident, a coordination in the expression of LeFRO1, LeIRT1, and LeIRT2 genes occurred already after 1 h treatment when the amount of Fe acquired by the plants from the three sources was similar. Iron from Fe- WEHS could be efficiently acquired in a mixture of natural Fe complexes possibly occurring in the rhizosphere. This phenomenon is due to an altered expression of Fe uptake- related genes and to the root capacity to create favorable conditions for the micronutrient uptake into the rhizosphere.
Titolo: | Physiological and molecular characterization of Fe acquisition by tomato plants from natural Fe complexes | |
Autori: | ||
Data di pubblicazione: | 2013 | |
Rivista: | ||
Abstract: | The aim of this work is to evaluate the capability of tomato plants to use different Fe sources, such as Fe citrate, Fe phytosiderophores, and Fe complexed by a water-extractable humic substances (Fe-WEHS) also in re- lation to physiological and molecular adaptations induced by these complexes at the root level. Tomato plants acquired higher amounts of Fe from Fe-WEHS than from the other two sources and this phenomenon occurred only when the treatment lasted 24 h. The higher acquisition of Fe from Fe- WEHS than other sources depended on a reductive mecha- nism and on rhizosphere acidification and appeared to be due neither to a higher apoplastic loading nor to a higher resistance of WEHS to microbial degradation. Supply of the different Fe complexes to deficient plants induced a tran- sient upregulation of Fe(III)-chelate reductase (LeFRO1) and Fe transporter genes, LeIRT1 and LeIRT2. In Fe- WEHS-fed plants, where a quicker and higher upregulation of these genes was evident, a coordination in the expression of LeFRO1, LeIRT1, and LeIRT2 genes occurred already after 1 h treatment when the amount of Fe acquired by the plants from the three sources was similar. Iron from Fe- WEHS could be efficiently acquired in a mixture of natural Fe complexes possibly occurring in the rhizosphere. This phenomenon is due to an altered expression of Fe uptake- related genes and to the root capacity to create favorable conditions for the micronutrient uptake into the rhizosphere. | |
Handle: | http://hdl.handle.net/11562/430289 | |
Appare nelle tipologie: | 01.01 Articolo in Rivista |